SUMMARY/ABSTRACT Fine-needle aspiration (FNA) cytology is the standard technique for evaluating thyroid nodules. Hemorrhaging is common during the procedure, however, leading to an aspirate that is significantly diluted by blood. Subsequent slide preparations are often suboptimal, resulting in nondiagnostic outcomes that necessitate additional testing or diagnostic surgery. In fact, quality is so unpredictable that a pathologist must often be present in the operating room to certify that the slides are adequate, thus adding substantial cost and complexity to the procedure. Ancillary testing such as immunocytochemistry and fluorescence in-situ hybridization can also be used for evaluating the aspirate, but such tests are not usually carried out using smears due to a paucity of follicular cells and an abundance of red blood cells. As a result, additional slides must be prepared using expensive and time-consuming techniques. Thus, there is a significant need for increasing the capture and isolation of thyroid cells on FNA slide preparations. Affinergy is developing a novel technology for improving the quality of thyroid FNA slide preparations. We have identified proprietary peptides that binds with high affinity to thyroid cells but not to red or white blood cells, and we have developed a cell-specific coating for glass slides that provides a simple, reproducible method for preparing optimal FNA slides from samples contaminated with blood. A reduction in non-diagnostic results will lead to improved quality of care and fewer unnecessary tests and diagnostic surgeries. At the conclusion of this Phase II project, we will have sufficient data in hand to rapidly bring our peptide-conjugated slides to market.